http://mjcce.org.mk/index.php/MJCCE/issue/feedMacedonian Journal of Chemistry and Chemical Engineering2018-06-28T07:15:40+02:00Zoran Zdravkovskizoran@ukim.edu.mkOpen Journal Systems<p>Print ISSN 1857-5552; Online ISSN 1857-5625</p><p>JCR Impact factor: <span style="font-size: 1em;">2017 - five year (2012-2016) - 0.538; </span><span style="font-size: 1em;">2017 (2015-2016) - 0.612</span></p>http://mjcce.org.mk/index.php/MJCCE/article/view/1407Friction mechanism of polymers and their composites2018-06-26T08:35:54+02:00Gordana Bogoeva-Gacevagordana@tmf.ukim.edu.mkDimko Dimeskidimko.dimeski@ugd.edu.mkvineta srebrenkoskavineta.srebrenkoska@ugd.edu.mk<p>This paper provides a brief review of the tribological properties of polymers and polymer matrix composites (PMCs) and the relevant mechanisms of friction and wear. The influence of both molecular and mechanical components on friction involving polymers as well as the influence of fillers, reinforcements and dry lubricants on the overall tribological characteristics of PMCs is evaluated. Tribological parameters include surface roughness, the mechanism of adhesion, friction and wear, and chemical interactions with dry lubricants (if present). The article reviews the main factors that influence the wear and frictional characteristics of thermoplastic and thermosetting polymers, short fiber reinforced composites and high-performance unidirectional composites. Examples of quantitative data of different pairs of polymers and PMCs with the counterface are presented.</p>2018-06-09T08:40:23+02:00Copyright (c) 2018 Gordana Bogoeva-Gaceva, Dimko Dimeski, vineta srebrenkoskahttp://mjcce.org.mk/index.php/MJCCE/article/view/1371Microwave-assisted synthesis of biologically active amide derivatives of naphthenic acids under neat conditions2018-06-26T08:35:54+02:00Ljubica Grbovićljubica.grbovic@dh.uns.ac.rsBojana Radovan Vasiljevićbojana.vasiljevic@dh.uns.ac.rsKsenija Pavlovićksenija.pavlovic@dh.uns.ac.rsTimea Hajnal-Jafarimikrobiologija@polj.uns.ac.rsSimonida Đurićsimonida@polj.uns.ac.rsMirjana Popsavinmirjana.popsavin@dh.uns.ac.rsSlavko Kevrešanskevresan@neobee.net<p>Within the field of green chemistry, a noticeable results were obtained in the solvent-free synthesis of amide derivatives of naphthenic acids under microwave irradiation. Naphthenic acid amides, anilides, and morpholides were synthesized directly from free carboxylic acids and amines in the absence of solvent and catalyst under high-temperature heating in a closed-vessel system of microwave reactor. With this new and efficient method, different primary, secondary, and tertiary amide derivatives of naphthenic acids were obtained in good to excellent yields. Synthesized derivatives were assayed as plant rooting agents for their stimulative effects on the formation of adventitious roots in sunflower cuttings and susceptibility for growth stimulation of <em>Pseudomonas</em> sp. strains.<em></em></p>2018-06-09T08:40:23+02:00Copyright (c) 2018 Ljubica Grbović, Bojana Radovan Vasiljević, Ksenija Pavlović, Timea Hajnal-Jafari, Simonida Đurić, Mirjana Popsavin, Slavko Kevrešanhttp://mjcce.org.mk/index.php/MJCCE/article/view/1334New multifunctional agents and their inhibitory effects on the acetyl cholinesterase enzyme2018-06-26T08:35:55+02:00Ali Dişliadisli@gazi.edu.trMurat Gümüşmuratgumus@gazi.edu.trKübra Önalkubraaa_unal@gmail.comNurşen Sarınursens@gazi.edu.trFatma Arslanfatma@gazi.edu.tr<p>A novel series of 2-((-1-substituted phenyl-1<em>H</em>-tetrazol-5-yl)thio)-2,3-dihydro-1<em>H</em>-inden-1-one compounds were designed, synthesized, and evaluated as multi-potent anti-Alzheimer drug candidates. First, treatment of various organic isothiocyanates with sodium azide in the presence of pyridine gave corresponding 1-substituted phenyl-1<em>H</em>-tetrazol-5-thiol compounds. Then, novel 2-((-1-substituted phenyl-1<em>H</em>-tetrazol-5-yl)thio)-2,3-dihydro-1<em>H</em>-inden-1-one compounds were synthesized by treatment of 2,3-dihydro-1<em>H</em>-inden-1-one with the 1-substituted phenyl-1<em>H</em>-tetrazol-5-thiol in the presence of I<sub>2</sub>. The synthesized compounds were characterized by spectroscopic methods. The inhibitory effects of the synthesized compounds on the acetyl cholinesterase enzyme (AChE) were then tested. An <em>o</em>-iodo substituent displayed higher activity compared to the other analogs. The <em>o</em>-iodo substituent showed a mixed-type of the AChE with an <em>IC</em><sub>50</sub> value of 1.75 μM. For the studied compunds all <em>IC<sub>50</sub></em> values for AChE were in the micromolar range.</p>2018-06-01T00:00:00+02:00Copyright (c) 2018 Ali Dişli, Murat Gümüş, Kübra Önal, Nurşen Sarıhttp://mjcce.org.mk/index.php/MJCCE/article/view/1406Isolation of Artonin E from the root bark of Artocarpus rigida, synthesis of Artonin E acetate and evaluation of anticancer activity2018-06-28T07:15:40+02:00Tati Suhartatitati.suhartati@fmipa.unila.ac.idHernawan Hernawannawani@gmail.comJhons F. Suwandiyadisuwandi04@gmail.comYandri Yandriyandri.as@fmipa.unila.ac.idSutopo Hadisutopo.hadi@fmipa.unila.ac.id<p>Artonin E was isolated from the root bark of <em>A. rigida</em>. The isolated compound was then esterified using a known procedure by the addition of acetic anhydride with pyridine catalyst. The structure of the synthesized compound was carefully determined by physical and spectroscopic techniques and compared to the data in the literature. The anticancer activity test against murine leukemia cancer cells P-388 showed that the ester compound has good activity with an IC<sub>50</sub> of 2.79 μg/mL and much better stability during storage compared to Artonin E itself.</p>2018-06-01T00:00:00+02:00Copyright (c) 2018 Sutopo Hadi, Tati Suhartati, Hernawan Hernawan, Jhons F. Suwandi, Yandri Yandrihttp://mjcce.org.mk/index.php/MJCCE/article/view/1287Application of Lactobacillus casei 01 and oligofructose-enriched inulin in ayran2018-06-26T08:35:55+02:00Tanja Petreska Ivanovskatpetreska@ff.ukim.edu.mkZoran Zhivikjzokorjk@yahoo.comLiljana Bogdanovskalbogdanovska@ff.ukim.edu.mkKristina Mladenovskakrml@ff.ukim.edu.mkLidija Petrushevska-Tozilito@ff.ukim.edu.mk<p>This study aimed to develop a probiotic/synbiotic ayran with a sufficient number of live bacteria <em>Lactobacillus casei</em> 01 (<em>L. casei</em> 01) during the product shelf-life. Under conditions of refrigerated storage for 15 days, probiotic survival and organic acid (lactic, acetic, propionic and butyric acid) production were evaluated. Simultaneously, pH, titratable acidity, total solids, and carbohydrate, protein, fat and mineral contents of the samples were examined. Overall results of the chemical analyses indicated the quality of the prepared samples to be comparable with the conventional ayran used as a matrix for probiotic/synbiotic supplementation. <em>L. casei</em> 01 survived better in ayran containing synbiotic chitosan–Ca–alginate microparticles compared to samples enriched with non-encapsulated probiotic alone or with synbiotic (<em>L. casei</em> 01 + oligofructose-enriched inulin), followed by increased production of lactic, acetic and propionic acid. Probiotic/synbiotic ayran may contribute to a healthy diet for consumers, while the sample enriched with microencapsulated formulation is advantageous in terms of probiotic activity.</p>2018-06-09T08:40:24+02:00Copyright (c) 2018 Tanja Petreska Ivanovska, Zoran Zhivikj, Liljana Bogdanovska, Kristina Mladenovska, Lidija Petrushevska-Tozihttp://mjcce.org.mk/index.php/MJCCE/article/view/1404Studies on heavy metal removal efficiency and antibacterial activity of 2-(diphenylphosphino)aminopyridine2018-06-26T08:35:55+02:00Özlem Sarıözozsarioz4@yahoo.comBurcu Malgaçburcu.malgac@gmail.comYavuz Sürmeysurme@ohu.edu.trSedef İlkilksedef@hotmail.comMuhsin Karaarslanmuhsinkaraarslan@gmail.com<p>The solvent extraction of metal picrates such as Ni<sup>2+</sup>, Cu<sup>2+</sup>, Co<sup>2+</sup>, Pb<sup>2+</sup> and Cd<sup>2+</sup> from the aqueous to the organic phase was studied using 2-(diphenylphosphino)aminopyridine (Ph<sub>2</sub>PNHpy). The effects of parameters including the pH of the aqueous phase and the ligand solution volume were investigated to determine the extraction ability of the ligand for metal ions. The results showed that the extraction percentages of metal ions were high at low pH values. The antibacterial activity of the aminophosphine was also screened against <em>Escherichia coli (E. coli) </em>ATCC 25922, <em>Staphylococcus aureus (S. aureus)</em> ATCC 25923, <em>Pseudomonas syringae pv. tomato (P. syringae)</em> DC300, <em>Salmonella enterica serotype Typhmurium (S. typhmurium)</em> SL 1344 and <em>Streptococcus mutans (S. mutans)</em> ATCC 25175. From the studies of antibacterial activity, it was observed that the ligand exhibited a potent inhibitory effect against all Gram-negative and Gram-positive bacteria with a diameter of inhibition zone ranging from 3.86 to 18.10 mm. The aminophosphine ligand (Ph<sub>2</sub>PNHpy) should be considered as a suitable bio-active molecule for antimicrobial material design and next-generation, non-toxic drug fabrication. The Ph<sub>2</sub>PNHpy obtained may have the potential for use as an antimicrobial additive for bioengineering applications.</p>2018-06-01T00:00:00+02:00Copyright (c) 2018 Özlem Sarıöz, Burcu Malgaç, Yavuz Sürme, Sedef İlk, Muhsin Karaarslanhttp://mjcce.org.mk/index.php/MJCCE/article/view/1421A 1:1 energetic co-crystal formed between trinitrotoluene and 2,3-diaminotoluene2018-06-26T08:35:55+02:00Nilgun Sennilgunsen2001@gmail.com<p>A 1:1 co-crystal of trinitrotoluene (TNT) and 2,3-diaminotoluene was prepared by solvent evapo- ration, and the structure of the co-crystal was determined by single-crystal and powder X-ray diffraction. The results indicate that the main mechanism of co-crystallization originates from the intermolecular hy- drogen bonding (amino-nitro) and π-π stacking. We also examined the Hirshfeld surfaces and associated fingerprint plots of the co-crystal and reveal that the structures are stabilized by H…H, O–H, O…O and C…C (π-π) intermolecular interactions. We analyzed the crystal packing and show its influence upon im- pact sensitivity. The results highlight that co-crystallization is an effective way to modify the sensitivity, oxygen balance and density of explosives.</p><p> </p>2018-06-01T00:00:00+02:00Copyright (c) 2018 Nilgun Senhttp://mjcce.org.mk/index.php/MJCCE/article/view/1442Covalent attachment of phenyl and carboxyphenyl layers derived from diazonium salts onto activated charcoal for the adsorption of pesticides2018-06-26T08:35:55+02:00Jeton Halilijeton.halili@uni-pr.eduFexhrie Salihufexha.salihu@hotmail.comAvni Riza Berishaavniberisha83@gmail.com<p>The past and recent uncontrolled use of organochlorine pesticides imposes serious problems due to their adverse undesired effects in ecosystems. Finding new ways to dispose of these molecules is therefore mandatory. The covalent modification of activated charcoal powder (ACP) by substituted aryl groups can be achieved by reaction with aryl radicals obtained through the sonically induced dediazonation of diazonium salts. Seventeen organochlorine pesticides were adsorbed on ACP covalently grafted with phenyl and carboxyphenyl layers. The sorption percentages of the pesticides onto the carboxyphenyl modified ACPs [measured by GC-ECD (Gas Chromatography – Electron Capture Detector)] were in the range of 90–100% (DDT, δ-HCH, γ-HCH and endrin aldehyde), 80–90% (methoxychlor, endosulfan II, <em>p,p</em>-DDD and β-HCH) and 60–80% (α-HCH, DDE, endosulfansulfate, endrin, endosulfan I, aldrin, heptachlorepoxid, dieldrin and heptachlor). A tentative explanation is given for these differences based on steric effects.</p>2018-06-01T00:00:00+02:00Copyright (c) 2018 Jeton Halili, Fexhrie Salihu, Avni Riza Berishahttp://mjcce.org.mk/index.php/MJCCE/article/view/1400The relationship between learning styles and students` chemistry achievement2018-06-26T08:35:55+02:00Stanislava Olićstanislava.olic@dh.uns.ac.rsJasna Adamovjasna.adamov@dh.uns.ac.rs<p>This research aimed to determine the chemical content which is the most challenging for students, and also to study the differences in chemistry achievement among students who prefer different learning styles. The study was carried out on the sample of 265 second grade students (aged 15–16 years) from seven grammar schools in Vojvodina (Serbia). Two instruments were applied in the study to determine the learning styles: chemistry knowledge test and Learning Style Inventory (LSI version 3.1). According to the findings, students have difficulty learning the contents of the topics Chemical Equilibrium, Salt Hydrolysis and Oxidation-Reduction Reactions. The findings show that there is a significant relationship between achievements in chemistry and students’ learning styles. The findings obtained in this research represent a step towards improving chemistry education since they identified the topics that students find it the most difficult to learn.</p>2018-06-09T08:40:25+02:00Copyright (c) 2018 Stanislava Olić, Jasna Adamovhttp://mjcce.org.mk/index.php/MJCCE/article/view/1424A safe way of performing dangerous experiments. III. The safety box. 1. Demonstrating the reactions of alkali metals with concentrated acids of the type HX(aq) (X = F, Cl, Br, I)2018-06-26T08:35:55+02:00Miha Bukleskimihabukleski@yahoo.comVladimir Petruševskivladimirpetrusevski@yahoo.comSlavica Aleksovaaleksovaslavica@gmail.com<p>Earlier publications of the series "A Safe Way of Performing Dangerous Experiments" were devoted to two instances of dangerous experiments and the applied approaches appeared to be safe enough for both the instructor and the audience. Here, we present the results obtained by systematic study of the reactions between Li, Na and K with concentrated water solutions of hydrohalic acids by using a safety box. Video clips of all experiments were prepared as an aid for those that lack experience and/or the necessary materials for safe performance of the demonstrations. Also detailed description and explanation of the observed phenomenon are given.</p>2018-06-01T00:00:00+02:00Copyright (c) 2018 Miha Bukleski, Vladimir Petruševski, Slavica Aleksovahttp://mjcce.org.mk/index.php/MJCCE/article/view/1490Годишно собрание на СХТМ 2018 година2018-06-26T08:35:55+02:00Зоран Здравковскиzoran@ukim.edu.mk2018-06-01T00:00:00+02:00Copyright (c) 2018 Zoran Zdravkovskihttp://mjcce.org.mk/index.php/MJCCE/article/view/1491Извештај од натпреварите по хемија за 2017/18 година2018-06-26T08:35:56+02:00Марина Стефоваmarinaiv@pmf.ukim.mk2018-06-01T00:00:00+02:00Copyright (c) 2018 Марина Стефоваhttp://mjcce.org.mk/index.php/MJCCE/article/view/1492First Humboldt Kolleg in Macedonia2018-06-26T08:35:56+02:00Valentin Mirceskivalentin@pmf.ukim.mk2018-06-01T00:00:00+02:00Copyright (c) 2018 Valentin Mirceskihttp://mjcce.org.mk/index.php/MJCCE/article/view/1493Impressum2018-06-27T07:55:01+02:00Zoran Zdravkovskizoran@ukim.edu.mk2018-06-01T00:00:00+02:00Copyright (c) 2018 Zoran Zdravkovski